Piston for internal-combustion engines.



A. WILLMER. PISTON FOR INTERNAL COMBUSTION ENGINES. APPLICATION FILED DEO.14, 1912.

1,065,289, Patented June 17, 1913.

Jm/e/zior:

combustion engines 35 members.

40 tened down in 55 the usual cylindrical side ARNOLD WILLMER, OI HANOVER-KLEEFELD, GERMANY.

PISTON FOB INTERNAL-COMBUSTION ENGINES.

Specificationpf Letters fatent.

Patented June 17, 1913.

Application filed December 14, 1912. Serial No. 786,863.

To all whom it may concern:

Be it known that I, ARNOLD WILLMER, a citizen of the German Empire, residing at Hanover-Kleefeld, Germany, have invent- 5 ed certain new and useful Improvement'sfin Pistons for Internal-Combustion Engines, of which the following is This invention relates to improvements in pistons especially the pistons of internal of the type in which the fuel is sprayed, with the aid of com pressed air, against theend of the piston. The invention is thus especially adapted for the pistons of Diesel oil engines. The temperature of the center part of the piston in such cases rises to a higher degree than the outer parts and owing to unequal expansion and cooling, internal strains of a complicated and serious character are set up.

central valve plate has also been found disadvantageous as the internal strains in this valve plate cause its edges to Warp. According to the present invention these objections and others are overcome by employing a cover plate on the piston which is held near its periphery by members which-permit of relative expansion between the cover and the end plate without straining the parts. To this end the cover plate is provided near its periphery with engaging members conveniently in the form of lugs in which holding members looselfy engage and a pressure in the direction he axis of the piston is applied to these holding A simple method is to employ engaging lugs on the cover plate near its peripher into which there fit the-heads of T-head bolts. These bolts may pass through plates within thepiston and be fasthe ordinary way.

The invention will be more readily understood from the following description of one convenient form illustrated by way of example in the accompanying drawings in of the cover plate used. Fig. 3, is a detailed sectional view on the line A--B of Fig. 2 and shows the shape of the lugs employed.

In carrying the invention into efi'ect according to the form shown the piston b, has walls 'b' and end wall 1;. In the end wall I) there is proa specification... v

means fitting loosely vided a central opening which is in turn closed by the cover plate a. The cover plate a, is a loose 'fit in a recess formed in the end wall I). This cover late is held tightl against its cl sur ace and the end we 1. b, by members a apted to exert axial pressure at a plurality. of oints near the riphery of the cover pllite a. These ho dmembers are adapted to loosely engage with the cover plate a, so as to allow of relative radial expansion and contraction between the cover plate a, and the end wall I), of the piston. In the form shown the cover plate a, is provided on its inner side and near its periphery with a plurality of lugs 0. These lugs in the form shown are of the kind used for takin T-headed bolts. T-headed bolts (1, fit with t eir heads in the lugs and pass through and are'fastened on to an internal plate 0, located within the piston. With this device the T-headed bolts (1, do not interfere with the radial or relative expansion of the parts while atthe same time they hold the cover plate a, at all points around its circumferencetightly against the closing'face on the end b of the piston.

I claim: 0

1. A piston having a cylindrical body and an end part having a central opening, a

cover plate loosely fitting in said opening,

and means between the cover plate and the I interior of the piston to hold the cover plate in position, said means and the loose fitting of the cover plate permitting relative radial expansion of the cover plate and the. end part.

.2. A piston having a cylindrical body and amend part formed with a central opening, a cover plate loosely fitting in said 0 ening, lugs extending from the inner sur ace of the cover plate, said lugs being wholly inside the piston, interlocking means between said lugs and the piston, the interlocking in the lugs, whereby to permit a relative radial expansion between the cover plate and the end part of the piston.

3. A piston having a cylindrical body and an end part formed with an opening, a cover plate fitting in the opening, lugs extending from the inside of the cover plate, each of said lugs having a T shaped slot, and T shaped bolts fitting loosely 1n the T shaped slots for securing the cover plate to the piston, the loose fitting bolts and cover Iiphe plate permitting of relative radial expansion between the end partof the piston and the end plate.

4-. A piston having a cylindrical body an end part having an opening therein, a cover on said opening, means located near the peand allowing of relative expansion of sai cover and end part for fixing said cover to said end part comprising lugs on the cover, T-headed bolts engaging in said lugs and a plate located within the piston.

5. A piston having a cylindrical body, an end part havi an opening approximately in the center t ereof, an annular shoulder within the piston body adapted to receive said cover, depending lugs upon said cover, bolts in said lugs, a plate within the piston body adapted to receive the bolts, and a shoulder in the said piston body adapted to receive said plate.

In testimony whereof I have signed my name to this specification in the presence of two subscribing Witnesses.

ARNOLD WI LLMER.

Witnesses MARIE BEHNE, FRAU RsnLER. 

